Cementitious compositions

ABSTRACT

AN IMPROVED CEMENTITIOUS COMPOSITION CURABLE BY HYDRATION AHD HAVING ENHANCED PROPERTIES, SUCH AS LESS WATER ABSORBENCY AND GREATER STRENGH, COMPRISES A CEMENTITIOUS MATERIAL AND A SMALL BUT EFFECTIVE AMOUNT OF ALKENYL SUBSTITUTED SUCCINIC ACID OR ANHYDRIDE.

United States Patent U.S. Cl. 106-90 7 Claims ABSTRACT OF THE DISCLOSUREAn improved cementitious composition curable by hydration and havingenhanced properties, such as less water absorbency and greater strength,comprises a cementitious 3,817,767 Patented June 18, 1974 from the airwhich is absorbed, e.g. during alternate freeze-thaw and wet-dryconditions.- Such uses include the construction of highways, bridges,docks, wharfs, pillars and supports therefor, curbs, sidewalks, dams,ramps, tunnel and shaft liners, barges and decks therefor, footings andfoundations, retaining walls, and masonry structures of various types.

In addition, it has long been known to improve the strength of earthsoil for hearing weight by mixing Port- 10 land cement or lime with thesoil under such conditions that the cement or lime hydrates and sets."The resulting soil, while not a building material comparable withPortland cement concrete, typically has load-bearing and otherproperties adapted to engineering uses much improved over unmodifiedearth soil. Such modification of soil in connection with constructionhas become a standard practice, available to the construction engineerwhen needed.

THE PRIOR ART The inventors know of no prior art that they deem mamialand a small but effective EB- significant. U.S. Pat. 2,770,077 isconcerned with the use stituted succinic acid or anhydride.

RELATIONSHIP TO RELATED APPLICATIONS The present specification andclaims are a continuation-in-part of co-pending application Ser. No.825,926 filed May 19, 1969, now abandoned, which was acontinuation-in-part of application Ser. No. 711,790, filed Mar. 8,1968, now abandoned; and of co-pending application Ser. No. 761,284filed Sept. 30, 1968, now abandoned, which, in turn, was acontinuation-in-part of earlier co-pending application Ser. No. 605,569,filed Dec. 29, 1966, and now abandoned.

BACKGROUND OF THE INVENTION Cementitious materials have long been usedboth as a. structural material and as a binder. Chief among thosematerials are the hydraulic cements. The term, hydraulic cement, as usedherein, means one which, when admixed with water (or brine) sets to asolid mass. Portland, aluminous, and pozzolan cements and mortar, lime,slag and high aluminosulfate expensive cements are illustrative ofhydraulic cements. Portland cement is by far the most widely used andreference thereto may be made herein as generally illustrative of thehydraulic cements.

Hydraulic cement is used by admixing it with water or an aqueoussolution to make a slurry which is emplaced as desired in a space orvoid or within confining forms and which thereafter sets to a solid massthrough a process of hydration which proceeds chiefly by forming a highstrength matrix of interlocking crystals. When the aqueous slurryconsists essentially of only the cement and water or aqueous iiquid(e.g. a brine) when set, it is known as neat cement but when such slurrycontains sand and optionally other modifiers, it is known as mortar andwhen it contains gravel as well as sand, the set mass is known asconcrete.

Among the many uses of hydraulic cement compositions is that requiringthe slurry to set in water or brine or in a high humidity atmospherewherein resistance to excessive absorption of water by the cementcomposition is important if the set cement is to have a long life. Ithas been well established that the greater the resistance to absorptionof water and to aqueous solutions of salts, such as are encountered inthe form of deicing materials, the longer the life of the concrete orcement. Scaling, spalling, pitting, cracking, and other indications ofdegradation of the concrete or set cement are greatly accelerated by theamount of water or brine, or of moisture of an alken l succinic com oundin conditioning soil for agricult u use.

U.S. Pat. 3,335,018 is concerned with soil stabilization,

25 and is directed to a mixture of an alkalignetal ilicate, a loweralkanoigggigl gge; and 8111mm such as portland cement in soil, the saidmixture being taught to confer stabilization properties upon the soilsuperior to those of the hydraulic cement alone.

U.S. Pat. 3,202,521 teaches the use of sgdium dioctyl sulfosuccinate asan additive to a mix e o por an mm and aggregate as an air detrainingagent, useful to control the amount of entrained air retained within amixed concrete.

U.S. Pat. 3,131,074 is concerned with mechanical stabilization of soilsof unusually fine granular structure, and teaches the modification ofsoil stabilization by addition to the soil of a proportion of any ofseveral proteins together with any of several substantially basicmaterials such as por tl an d cement or an alw- U.S. Pat. 3,086,043 isconcerned with certain m ydride and certain r SW a 1,045 is concernedwith the stabilization of soil, and involves the modification of theconventional portland cement stabilization of soil by incorporation withit of an amount of a pine wood extractive resin.

SUMMARY OF THE INVENTION When a composition containing a cementitiousmaterial is modified, by the inclusion, in the chemical composition ofthe material, of an active amount of an alkenyl succinic acid compoundsas herein defined, the structural 65 properties of the material areimproved, as to ability to withstand various degradative effects,notably those involving intrusion or migration of water, or formation orgrowth of ice crystals. Improved ability to withstand other degradativeeffects is also noted when correspond- 7 ing degradative influences arepresent, including ability to withstand weathering, and notablyweathering that is enhanced by the presence, in atmosphere, rain, andthe like, of mineral acid anhydrides in exalted amounts, that is to say,in amounts made greater than normal as a result of combustion of carbon,sulfur, phosphorus, and so forth. Improved ability to withstand otherdegradative influences is noted, as well, including the withstanding ofvarious germicides in mop waters, and. the like.

This improvement of properties, while uniformly occurring throughout thescope of this invention, oftentimes takes different apparent forms indifferent environments.

The hydraulic cement is understood to include the portland cements inthe conventional and commercial sense, and may be of any of the standardcement types I, II, III, IV, or V (which are sometimes designated by thecorresponding Arabic numerals). Also comprehended in the instanthydraulic cements are the aluminous cements, the pozzolan cements, themortars, lime, plaster, Plasterof-Paris, and its special formscontaining wood flour and sometimes called water putty; slag cements andthe expansive cements of high aluminosulfate content.

Lime as employed in the instant specification and claims is a calciumoxide or hydroxide form susceptible of hydration from finely powderedform, with water, whereby it sets and hardens from a loose powder to acontinuous solid: and Plaster-of-Paris is the calcium sulfate withsimilar properties of hydration.

The active agent is an alkenyl succinic anhydride of the formula or analkenyl succinic acid or salt of the formula in either of which formulaeat least one G represents alkenyl of from 6 to 16, both inclusive,carbon atoms, the other G independently represents hydrogen or alkenylof from 8 to 16, both inclusive, carbon atoms and either R isindependently hydrogen, ammonium or alkali metal. Thus, the half saltsare herein included, as salts.

The substituted succinic acids, salts, and anhydrides to be employed asactive agent in the present invention are, in general, articles ofcommerce or are made by procedures substantially identical with thoseemployed in manufacturing the articles of commerce, such as the reactionof an olefin with maleic anhydride, followed by, if desired, hydrolysis,or neutralization or both.

The position in the alkenyl chain of the ethylenic unsaturation that ischaracteristic of alkenyl moieties is not critical. The invention ispracticed successfully when employing an isomer in which the ethylenicposition is precisely known and the purity is high; results when usingsuch pure materials, in the present invention, are essentiallyindistinguishable from results obtained when employing industrial mixedisomers in which location of the unsaturation is not known. Also,mixtures of alkyl and alkenyl substituted, and mixtures of anhydride,acid and salt, or any two of them, so long as adequate amounts ofalkenyl succinic anhydride are supplied, work as well as pure materials.

Among the compounds that are articles of commerce and are usable in thepresent invention are the following: a mixed hexadecenylsuccinicanhydride represented by the manufacturer as being an isomeric mixture;a relatively pure l-decenylsuccinic anhydride having a refractive indexn at 20 C. for the D line of sodium light of 1.4691; a mixeddodecenylsuccinic anhydride as a viscous liquid 4 boiling at 180-182 C.under 5 millimeters mercury pressure absolute; a purel-dodecenylsuccinic anhydride as a crystalline solid melting at 38-40"C.; a l-hexadecenylsuccinic anhydride melting at 59-60 C.; atetradecenylsuccinic anhydride melting at 53-565 C.; and a 1,l,3,5-tetramethyl-Z-octenylsuccinic anhydride, supplied as a viscous yellowliquid.

Other substances equally adapted to be used include octenyl succinicanhydride and didodecenylsuceinic anhydride.

Any of the foregoing can, if desired, be hydrolyzed to obtain thecorresponding acid, and, if desired, neutralized with ammonia or analkali metal hydroxide or the like to obtain a corresponding salt andthe resulting product used successfully in this invention. The sodiumsalt is preferred as least expensive, but the lithium and potassiumsalts can also be used. Representative such succinic acid compoundsinclude l-hexadeoenylsuccinic acid, melting at 69- 71'C. and the otherhomologues within the indicated scope.

The aggregate to be used in a concrete of this invention may be any goodaggregate for concrete of the prior art. Such aggregate is inclusive ofnatural sand and gravel, from stream beds, terraces, flood plaindeposits, alluvial fans and cones, marine deposits, glacial deposits,crushed, quarried bedrock materials, talus, coral, blast furnace. slag;such light-weight aggregates as pumice, volcanic slag (scoria), orvolcanic cinders.

Also such manufactured light aggregates as expanded shales, clays,slates, slags, and clinkers, and perlite, expanded vermiculite, andfoamed glass are of value as aggregates to be used in this invention.

In one aspect, the aggregate is earth soil. The soil type is notcritical, and the locale of the soil treated according to the presentinvention is not critical. It is assumed that such soils will at leastpart of the time contain some natural soil moisture. The soil can beexposed, or exposed in part, as a steep embankment adjacent a cutthrough a hill, where it is desired to control gulleying and washing ofsoil; it can be buried as under the foundation of a building or beneatha paved road; it can be in a situation normally exposed to high watertable as in the earth behind rip-rapping along a river bank; or earthfill surrounding a stone well. The modified soil can be buried at a moreor less uniform depth of from about 4 to about inches, typically about18 inches, beneath the surface of an agricultural soil, where it canfunction as a barrier to drainage, to improve retention of soilmoisture. It can be cut into orderly pieces that are then used asbuilding blocks; or such blocks can be preformed in molds of desiredshape and size. Such blocks can then be used for paving, rip-rapping instructural walls, and the like. The location and exposure of the soiltreated according to the present invention are matters essentially ofindifference in the present invention.

The rock-like mineral aggregate concretes of this invention are ofspecial advantage as an exposure-surface layer of, or to constitute thewhole mass of, a concrete article including such structures as highways,bridges, docks, wharfs, pillars and supports therefor, curbs, sidewalks,dams, ramps, tunnel and shaft liners, barges and decks therefor,footings and foundations, retaining walls, and masonry structures ofvarious types.

The advantageous properties of all aspects of this invention pertainespecially to withstanding the degradative effects of brines, includingsea water, sea water diluted with terrestrial surface water as in thewaters of major bays; mineral well brines, brines artificially formed bythe use of calcium and sodium chlorides and similar ionic salinematerials in control of snow and ice, and the like.

The moistening or wetting of a dry mixture of this invention calls forthe use of water. Such water and its use follow the prior art, as topurity, quantity, temperature, manner of addition and the like, and goodprior art practice is of use here.

Components employed in the present invention are used in practicewhether naturally moist, air dry, or oven dry. However, for uniformity,all weights stated herein, unless otherwise stated, are oven dryweights. Oven dry implies drying according to Procedures for TestingSoils" (American Society for Testing Materials, Philadelphia, 1958) p.102, 103, method D-698-57T. The oven is thermostatically controlled at110 C.i-5 C., for 24 hours, under atmospheric pressure, with constantchange of air. Further drying results in no further loss of weight.

The substituted succinic anhydride or acid or salt may be incorporatedinto the other components of the hydraulic cement mixture in anyconvenient way. In one manner, the dry active agent is first dispersedin the dry cement (or burned lime or the like) before it is admixed withthe aggregate. In another way, the active agent is first dispersed inwater and the water used to moisten a mixture of aggregate and cement.In another method, the active agent is distributed, dry or in aqueous orother dispersion, over the aggregate, notably when it is an area of soiland worked into the soil with tillage instruments, and the cementadditive applied thereafter. Other methods can be used. However added,the active agent is to be added so as to be distributed essentiallyuniformly and at approximately the time the mixture of all components ofthe present invention is prepared and compacted or otherwise finishedfor use throughout so much of the entire mass as is to represent theadvantages and benefits of this invention.

Compositions of the present invention comprising active agent in anamount less than about 0.025 percent by oven dry weight of cementitiousmaterials have upon hydration and setting, properties that differ onlymarginally from those of hardened hydraulic cement materials with noactive agent. Compositions of the present invention comprising activeagent in an amount greater than about 5 percent, same basis, have littleor no advantage over compositions containing 1 percent or somewhat less.Good results are obtained from compositions comprising 0.25 percentactive agent by dry weight of cementitious material. Good results areobtained when using 0.003 percent active agent by weight of oven drynon-water components. Thus preferred amounts of the active agent arefrom about 0.025 to about 0.25 percent by weight of cement. Amounts ofportland cement of from 2 to 16 percent by oven dry weight of soil giveexcellent results.

In some situations, it will be preferred to incorporate the active agentalltenyl succinic acid compound into the composition after the materialhas been brought to a structural shape or form or position; and in manysituations it is impossible to incorporate the active agent into thestructural composition beforehand.

Thus, when desired, the active agent is readily dispersed in a liquiddispersant, which is usually most conveniently a solvent within whichthe active agent is dissolved; and such dispersion, which can usually bea solution, is applied as spray, swab, wash, dip, or the like to anouter surface of the structure made from the cementitious material whileoftentimes such structure is in the shape of a slab, floor, pediment,cornice, pedestal, relief, statue, decorative carving, pillar, capital,buttress, muntin, mullion, tympanum, or the like. In the instance ofsuch disposition of structures as calls for subsequent finishing, suchas, for example, the grinding and polishing of a terrazo surface, it ismuch preferable to complete such finishing before applying compositioncomprising essentially an active amount of an active agent according tothis invention.

When applying active agent of this invention from solution or the like,water can be used as solvent if desired. However, better penetration ofthe surface of a structure is obtained when using a preferred organicsolvent. A preferred organic solvent is one that is characterized asbeing essentially without humectancy, having no hydroxyl groups, readilyand completely volatile, of low surface tension, adequately effective assolvent for the active agent, and, in many applications for estheticreasons, absence or substantial absence of color of its own, toxicityand flammability within tolerable levels, and acceptable odor if any.

Thus, the lower alkanols are not to be employed, the glycols andglycerine are also contraindicated.

Solvents that give excellent results include acetone,1,1,1-trichloroethane (which can be corrosion-inhibited as to metalcontainers and the like, if desired) any of various light to mediumboiling mineral spirits, various volatile paint and lacquer thinners,toluene, benzene, xylene, the solvent esters such as amyl acetate; mostof the lower alkyl ketones including methyl ethyl ketone, methylisobutyl ketone, and so forth. Also dichloromethane trichloromethane,1,2 dichloro 1,l,2,2 tetrafluoroethane. monofluorotrichloromethane, andthe like.

On the inventors experience to this time, the most preferred solventsinclude water, 1,1,1-trichloroethane, and light mineral spirits.

in applying active agent in solution in nonaqueous solvent, preferredpractice will be to apply solvent solution to dry or substantially drycomposition to be treated, whereby solvent can penetrate to a maximumdepth, permitting solvent to disappear, largely by spontaneousevaporation, and thereafter exposing the resulting treated compositionto water vapor. Water, in some way, appears to be necessary to cause, orpermit, some necessary interaction between active agent and the alkalineearth metals of the cementitious material; and better results appear tobe achieved when first water contact following treatment is with waterin vapor phase. However, this is not critical, good results beingobtained when water is brought into liquid phase contact with treatedcomposition.

It is noted that the necessary water contact is made simultaneously withany first exposure of treated composition to water-involved degradativeinfluences.

Also, it is sometimes preferred to apply solvent solution of activeagent as a two-phase, or polyphase emulsion or suspension. In thissituation, either organic or aqueous may be the continuous phase, andthe other the discontinuous phase; and usually active agent will tend topartition between the phases as a function of its relative solubility ineach. Thus, each phase functions in such polyphase dispersion.Evidently, then, it is immaterial whether such dispersion be thought ofas a solution, or as two solutions, or as an emulsion. This is of valueparticularly when employing an invert emulsion of relatively enhancedviscosity; that is, an emulsion in which an organic phase, such as aphase based upon a petroleum fraction, is the continuous phase.

Other materials have been employed as additives to, particularly,portland cement and its mortar compositions. Among these are calciumstearate, oleic acid; various aqueous latexes of organic polymers, andso forth. These can be used in, or in conjunction with, their knownapplications in cement, concrete, mortar, lime, plaster, and the like,as heretofore, while the present invention is practiced conjointlytherewith.

Among the particular embodiments contemplated according to thisinvention are the modification of gypsum plaster including its form aspatching plaster, and its form as a paper-covered and at timesglass-fiber-reinforced central core in a wallboard or mineral lath orunderlayment for mineral lath; the hydraulic cement vehicle for holdingstucco in its various forms in place in a structure; fabric-reinforcedcasts of plaster of paris (kilned calcium sulfate) for surgical andrelated uses especially where degradation from aqueous liquids is aforeseeable problem; plaster models of statuary intended to be recast inbronze; clays and argillaceous earths modified by addition of calciumcompounds: and interior cement mortars of the magnesium oxychloridetype.

The following specific examples illustrate the best modes of practicingthe present invention,

an Q Example 1 With thorough mixing and stirring together, 1020 grams ofan air dried silt loam soil (979.3 grams, oven dry basis) wereintimately combined with 68.5 grams dry portland cement. Mixing andstirring were continued as the soil-cement mixture was brought to adesired moisture content (presently, 18.5 percent) by spraying with 153grams water. When the mixture was uniformly moist, twelve aliquots eachof 85 grams were taken, and, in a molding tube millimeters in diameter,were compressed from both ends in a hydraulic press until dimensionalstability was attained under pressure of 51.8 kilograms per squarecentimeter (740 pounds per square inch). There resulted from each of thetwelve aliquots so treated, a firm, self-supporting cylinder. Thecylinders were placed in an atmosphere of 100 percent relative humidityat room temperature to hydrate and cure. This procedure yielded twelvecylinders, each 3 by 6 centimeters, containing portland cement in theamount of approximately seven percent of the oven dry weight of thesoil. These were regarded as the untreated check samples, and arehereinafter called "Group 1."

Promptly upon completion of the preparation of the check samples,essentially the same process was repeated except that the water appliedas a spray contained ndecenylsuccinic anhydride in the amount of 0.25percent of the oven dry weight of employed soil. The twelve resultingtest cylinders, of appearance essentially indistinguishable from those,foregoing, were placed to cure with the test cylinders. This group ishereinafter called Group 2.

The process was repeated except that the n-decenylsuccinic anhydride wasemployed in the amount of 0.1 percent by weight of oven dry soil, andthe resulting cylinders hereinafter called Group 3."

The process was again repeated except that the ndecenylsuccinicanhydride was employed in the amount of 0.025 percent by weight of ovendry soil, and the resulting cylinders hereinafter called "Group 4.

Each group of cylinders was identified for later reference, andmaintained under 100 percent relative humidity to cure, for seven days.

At the end of the seven day curing time, random representativecylinders, four from each ditlerent group, were removed and air driedfor 24 hours, and thereafter immersed in water for 24 hours. Followingthe 24 hours water immersion, each group was tested for unconfinedcompressive strength (UCS).

The present and all other Unconfincd Compression Strength tests werecarried out in a standard, commercial unconfined compression strengthtester. In the tester, the cylinder is positioned with its flat endshorizontal, one resting on, and the other supporting, a pressure platewith a strain gauge actuated by deformation of a proving ring toindicate pressure between the plates. A screw mechanism with mechanicaldrive closes the distance between the pressure plates at a predeterminedrate, presently 0.05 inch per minute.

In tests of materials such as the present cylinders, pressure betweenthe plates rises more or less linearly until shear begins to occurwithin the cylinder material, at which point the rate of pressure risedeclines. This is usually soon followed by the collapse of the cylinderof tested material, ideally into cones one with a base on each pressureplate, meeting, or approximately meeting at a midpoint of the imaginaryaxis of the original cylinder. The pressure reading between the platescollapses immediately to zero, thus affording a satisfactory end point.The highest pressure attained before such collapse is regarded, forpurposes of the present tests, as the unconfined compressive strength ofthe material: being a point beyond 8 incipient shear it might not be asatisfactory norm for engineering design.

In the present example, the results obtained were as follows:

TABLE 1 Group: UCS, as lrg./cm.' 1 16.59 2 28.35 3 27.93 4 26.74

Example 2 With intimate mixing and stirring together, 425 grams of anair dried silty clay soil (408 grams, oven dry basis) was intimatelymixed and blended with 12.25 grams (3 percent of dry soil weight) ofcommercial burned lime of high calcium content, 98 percent calciumoxide. Mixing and stirring were continued as 72 grams water were sprayedon to the mixture, and a uniform moist mixture was achieved.

Aliquots of the resulting mixture were molded under hydraulic pressureexactly as described in Example 1, to obtain cylinders approximately 3centimeters in diameter and 6 centimeters in axial length. The testcylinders, regarded as checks, untreated, are hereinafter identified as"Group 5."

The process was repeated except that the water sprayed on to the limeand earth mixture contained an amount of n-decenylsuccinic anhydrideequal to 0.1 weight percent of oven dry soil (0.41 gram).

The resulting cylinders are hereinafter identified as "Group 6." Thecylinders of both groups were double wrapped in aluminum foil and heldfor 10 days at 60 C. to cure.

Upon completion of the curing period, representative cylinders from eachgroup were unwrapped, removed from the curing oven, and air dried for 24hours, then immersed in water at room temperature for 24 hours andthereafter tested for unconfined compressive strength. The resultsobtained were as set forth in the following table:

TABLE 2 Group: UCS, as ltg./cm. 5 19.95 6 24.78

Essentially the procedures of Example 1 were repeated, except that theadditive, portland cement was employed in the amount of 4 percent byoven dry weight of soil. Samples were prepared with no active agent(hereinafter Group 7) and with 0.13 percent tetradecenylsuccinicanhydride by weight of oven dry soil, hereinafter Group 8. The resultingtest cylinders were cured for 7 days at 100 percent relative humidity,air dried for 24 hours, and then immersed in water at room temperaturefor 24 hours, and thereafter tested for unconfined compressive strength,in the manner hereinbefore described.

The results are as set forth in the following table:

A parking lot in an area of sandy loam soil is improved according to thepresent invention, all operations being carried out in early summer. Thesoil is first tilled uniformly to a depth of six inches, measured fromthe original, undisturbed soil level. Portland cement is uniformlyspread over the tilled surface in the amount of 42.3 pounds, average,per square yard.

The soil is then watered with an amount of water calculated, withallowance for natural soil moisture present, to bring the moisturecontent of the soil, to tillage depth, to 14 percent moisture, total.The water added contains, dissolved, as active agent, disodiumoctenylsuccinate in an amount sufiiciently to supply 0.25 pound ofactive agent per square yard. Application of water without active agentis made, at the same water rate, to a marginal area maintained as acheck. The soil is then again vigorously tilled with a rotary tiller toachieve thorough mixing together of the soil, portland cement, water,and active agent, to the Original tillage depth. The area is thereafterleveled with a grader blade, compacted by repeated passages of asheepsfoot roller, and finished with a smooth roller. The area isthereafter maintained free of traffic for a week, as the soil mixturecures and attains strength. It is thereafter put into use.

In compression tests applied after a heavy rain several weeks later, aplug drilled as a core from the main parking lot area is found toexhibit approximately twice the unconfined compressive strength of asimilar core taken from the marginal area not treated with the activeagent.

Example A greased rectangular wooden mold is provided, 22 inches long,18 inches wide, inches deep, within. The size is intended to represent24 x 18 x 12 with an inch mortar joint allowance.

It is neatly filled with a composition of Group 2, Table 1, Example 1,foregoing. The material is permitted to cure and is then pressed out.The process is repeated to obtain a supply of blocks adequate for theconstruction of a test building.

As foundation footing, the earth is prepared according to Example 4,foregoing. It is graded to provide drainage away from the building inall directions.

Using standard broken joint construction characteristic of the laying ofunreinforced concrete block walls, with further composition of Group 2,Table 1, Example 1, freshly prepared, as mortar, a building 10 feetsquare is laid up with walls 9 feet high, with a 3 foot by 4 foot windowopening in each of two walls and, by sawing blocks with a masonry saw asnecessary, a door opening 30 inches by 84 inches in a third wall. Overthese openings, standard quarter inch by 3 x 8 T-iron lintels areprovided. The wall is plastered with hydrated lime plaster inside,outside, and on top. When the plaster is partially set, a 2 x 12 plateis embedded in it on top of the wall, encircling the wall, and flushwith its outer surface. Two x four collar beams are provided, to spanthe top opening and, cooperating with the collar beams, rafters areerected, meeting at facing tops and without ridgepole. Over the raftersa roof deck of inch plywood is laid. The rafters and deck extend beyondthe walls they overhang for 24 inches on each side, and the roof isswung by cantilever of the unsupported plywood ,finished with a 2 x 4fales rafter, to extend 24 inches beyond the wall at each end.

Steel casement windows are fixed into the window openings and a doorframe and door into the door opening. Remaining surfaces are thencaulked with further freshly prepared composition as used for mortar,and it, too is plastered over.

The biulding is exposed to ambient weather in climate in a wet regionnear the 30th parallel, north latitude. After two years with about 120inches of rainfall, total, it shows no evidence of structural impairmentor weakness.

a different kind of block. The blocks are like those, foregoing, exceptthat, in each case, approximately half the earth, by volume is removedfrom the block-making material and replaced, equal volume with, in onewall sawdust, in a second wall ground Styrofoam polystyrene foam, in athird wall foamed slag, and in the fourth wall coarsely ground bagasse.The blocks are well compacted, in each case, by vibration; but they arenot formed under high mechanical pressure.

To the workman erecting the walls, the blocks in this example are allconspicuously lighter in weight than those in the foregoing example. Atthe end of the two-year observation period, the building of thisexample, and each of its four walls in particular, appear in tact, freefrom evident deterioration.

The following examples were carried out in series.

' SERIES I Various cured, solid, neat cement plugs were prepared bypreparing a slurry of water and neat cement and, in one sequence of theseries, adding n-decenylsuccinic anhydride in the amount of 0.25 and ina second sequence in the amount of 0.50 parts by dry weight of portlandcement and thereafter curing in disposable cups. These sequencesinvolved various levels of water-to-cement weight ratio. The resultingplugs were aged for 28 days at 100 percent relative humidity, for 14days at 50 percent relative humidity, then weighed, and thereafterimmersed in water for 28 days and thereafter reweighed, and weight gainfrom water absorption calculated as percent of original weight. Theresults were as set forth in the following table.

TAB LE 4 Water-to-cement ratio-- Percent water absorbed, 28 days Percentndecenylauccinlc antigdri e The amount of water absorbed by theuntreated samples is clearly greater at all proportions of water/cementemployed but that the most effective performance of the invention was atthe lower water/cement ratios. It is well known that, for most uses, thericher or more highly concentrated cement slurries are preferred becauseof the greater compressive strength values and the lower permeability.This emphasized the importance of a low water/cement ratio as theconditions of freezing become more severe. Only sufficient water isrecommended to be used to insure adequate manipulability and subsequenthydration of the cement.

The water/cement ratio is not highly critical, but observation ofproperties of the slurry and set cement of the invention indicate that aratio of 0.316 typifies a practical utilitarian ratio having excellentfluidity and adequate strength properties and will usually be usedhereinafter. However, such ratio is merely as illustrative and any ratioof 0.25 to 0.60 is acceptable.

SERIES H In this series, the samples were prepared, as in Series I, butall having a water/cement ratio of 0.316. Four groups of tests wereconducted on the samples representing levels of n-decenylsuccinicanhydride of 0.10, 0.25, 0.50, and 0.75 percent expressed as inSeries 1. Each group was tested as to weight gain after 28 days totalimmersion in, respectively, water, 10% NaCl brine, and 10% CaCl, brine.The results obtained are set forth in Table 5.

TABLM acid but almost no spalling in the samples prepared (Percentweight gain of neat cement at various ASA levels from absorptionaccordmg to the Invention oiwater and brines,28-dayimmersion] SERIES IVn-Decenylsuccinic anhydride as percent dry cemem- 5 In this series oftests, mne aqueous portland cement 0,10 .2 0, test slurries, of a ratioof water/cement of 0.316, were Immersion P t i m m 1 prepared. The testcompositions consisted of three groups Example quid 7 E U of three testseach: Tests in Examples 17, 18, and 19, ii: :;-l :E l 1 0% 7Z4 512 312511 they consisted of cement and water only; m Examples 12 245 10 20, 21,and 22 they consisted of cement, water, and

0.25% by weight of oleic acid; in Examples 23, 24 and 25 they consistedof water, cement, and 0.25 by weight of n-decenylsuccinic anhydride(i.e., ASA). Specimens of each numbered test were poured and curedalike. One test specimen of each group, Examples 17, 20, and 23, wasimmersed in water; a second test specimen of each group,

Reference to Table 5 shows that as the amount of additive is increasedfrom none to 0.25 part, based on 100 parts dry weight of cement, theamount of immersion liquid absorbed decreases markedly but thereafterthere is little change in the amount absorbed, except, in the case ofwater, the amount absorbed actually increases to a measurable extent asthe amount of additive is increased Examplcs and 24 was m 10% by WightNaCl brine the third test specimen of each group Examabove 0.25 percentby weight of the dry cement. However, i n the amount absorbed is stillabout 2% lowerinabsorption Ples and 25 was lmmersid 10% by Wclght CaClbrine. thanmthe unmated cement Th: purpose of this series was to showthe relative SE ES I results obtained when neat cement samples areimmersed This SCI-ks of tests was run to Show the fi t f in variousaqueous media to ascertain the extent of alternating 24-hour periods ata temperature of 0' F. absofpnon and consgqumtlal 56 days and 48-hourperiods at room temperature (about 75 F.) 25 merslon- "suits of tests asform in air on four groups, comprising aqueous neat cement Tablc samplesas follows: one group was prepared afcording TABLE7 to the inventioncontaining 0.1% of n-deceny succinic acid anhydride and designatedExample 13, and three Abwptmnflmem daysgroups designated Examples 14, 15and 16. The group of 1 14 23 56 Example 14 and groups of Examples 15 and16 consisted Example numbers (See text Water or brine absorption wgt. ofsamples containing 0.25 and 0.50% oleic acid, respecand mama) swimtively, according to known practice in prior art attempts as 7.2 7.0 8.8to lessen water absorption. Water was used, as above, g in this seriesof tests in a water/cement ratio of 0.316. sfe e10 0:95 The tests wereconducted by preparing examples as in 22 g 5 1 g-: 3-? Series II aboveexcept the procedure was modified as 23 as abs 4.? 5:0 necessary toinclude the variations in the type and amounts is 2:5; 2::

of additives employed according to each group of tests in this series.The poured samples, upon setting and curing, Reference to Table 7 showsthat those compositions as indicated, were weighed and thereafterimmersed in ported in Examples 2345, employing the alkgnyl 10% Caclflbrme: removal themfi'omt rewighdi and cinic acid anhydride according tothe invention absorbed then subjected to the cycles of a freeze-thawtest, which l water or brine than those cmploying oleic acid as testconsisted of subjecting the Samples containing the additive or thosewherein no additive to lessen absorpsorbed CaCl: at alternatingtemperatures, of 0 F. for 24 tion a used. hours and room temperature (75F.) for 48 hours for SERIES V 10 cycles, each full cycle, therefore,lasting 72 hours. The samples being tested were carefully examined aftereach cycle for scaling and spalling. The results are shown in Table 6,which shows percent brine absorbed, and the 50 number of cycles of thefreeze-thaw treatment. The type of cement treatment is identified byExample number,

This series of tests was conducted to show the effect of a test whereindry, and brine-wet periods in successive cycles were alternated tocompare untreated samples with samples containing an alkenyl succinicacid anhydride, as illustrative of the practice of the invention. Thetests involved preparing and curing neat cement samples as in foregomg-TABLE 6 the foregoing series of tests, two, designated Examples 26Numberonz houflreeze maw was? and 27, were untreated, 1.e., conta ned noadditive for comparison purposes, and two, designated Examples 28 ggfi g0 1 2 3 4 5 6 7 and 29, contained 0.25%, by weight of the composition,(See ten) percent CBC], brim, absorbed of n-decenylsuccinic acidanhydride. Each sample was sub jected to a cycle beginning with 48 hoursin dry air at a room temperature of 75 F. Thereafter those of Examples26 and 28 were immersed in 10% by weight NaCl brine and Samples 27 and29 were immersed in 10% by weight Reference to Table 6 shows that theuntreated samples C3012 Each such W was repeatcd 1 sand those treatedwith 0161-: acid both by admixture Selected percentage absorptionfigures obtained are thereof with the aqueous cement slurry and byapplica- Table tion of a solution thereof to the exterior of the setcement TABLE 8 sample absorbed appreciably greater amounts of the[Abwpmnmm brine (although the oleic acid-tested samples showed Examplenumsome improvement over untreated) in comparison to the ,f'g gg gfggNumb Gyms" relatively low percent of absorption manifested by the :523;and 1 2 a 4 5 7 11 10 samples prepared according to the invention.Visual ex- Brine absorbed, wel ht rcent of earn 1 amrnatron of thevarious cement samples following each g pa p8 freeze-thaw cycle showedprogressive increased spalling I 2:2 2;; 3:3 9? 1'2 and decay of thecement of those samples which were un- 15 1 1 0 0.9 0.2 0.1 treated andto a lesser extent of those treated with oleic 29 In this series,samples of concrete were prepared, employing a water-cement-sand ratioof 0.515-l2.75, respectively, each sample but one modified by anadditive. The samples were prepared in disposable cups and cured, thecups removed and the samples thereafter air dried, weighed, immersed inwater for 56 days, reweighted, and gain of weight of absorbed watercalculated.

The mixtures employed, and the percent weight gain measured were asfollows:

TABLE 9 Amount as percent dry Immersion time, dayscement and compositionExample of additive 1 8 14 28 56 4. 4.1 4. l5 6% olelc acid posttreatment 8. 45 4. 0 4.15 4 26 4. 85 82 0.25% calcium stearste 2. 85 8.8 I. 5

tncoTorstod. 88 0.25% BAincorporated.... 1.86 2.1 2.6 2.7

Only Example 33 is illustrative of this invention. Water absorption inthe example is conspicously lower than in the three parallel prior artexamples.

Example 34 The instant invention is tested in the resurfacing of thedeck of a concrete surface bridge that conveys a motor vehicle highwayacross a railroad track, a river, and part of a flood plain adjacent theriver, the deck being recurringly exposed to rain, ice, and snow-controlsalts.

The repair is to be carried out according to good, modern techniques. Insurface preparation, all areas are scarified to remove at least 84 inchof surface and with it all oil pan drippings and anti-spelling oil;seriously damaged surface spots are cleaned to the depth of soundmaterial; reinforcing rods are cleaned or replaced, as indicated;regularly cut walls are provided toreplace irregular walls of cracks;and all areas to be repaired are cleared to /2 inch below screed line.All wet saw slurry is removed, and, immediateiy before placement of themodified hydraulic cements the surface is airor sand-blasted to leave aclean surface; the clean surface is then soaked with clean water for anhour and at that juncture, at a temperature between 45 and 85 F.,placement of repair concrete is begun.

Over about half the bridge surface, from the expansion joint at oneapproach to the expansion joint nearest its mid-length point, issurfaced in approved manner with a patching cement of superiorcharacteristics p'epared by the recipe Component Quantity Portlandcement, class I lbs.... 94 Sand cu. ft 2.5 Crushed stone cu. ft 2.0Latex -gallons.. 3.5 Water -do 3.5

The latex is a styrene-butadlene latex, 46-49 percent solids by weightof latex, poststablllzed with nonionlc surfactants and of a pH of 10-11.

Amount of water adjusted to give a finished actual total water/cementratio of 0.35414, allowing for aggregate moisture, etc.

The prepared concrete to be repaired is, in every instance,surface-brushed to assure intimate contact of at least the slurry fineswith all exposed surfaces to receive the repair: at once thereafter andbefore any surface drymg, the bulk of the concrete is deposited and isstruck off to about A inch'above final grade, consolidated withvibrating screeds, and hand-finished with a wooden float.

The resulting surface is textured by transverse strokes of a palmettobroom; at a suitable time screed rails and construction dams areremoved, and, upon formation of a surface latex film and as soon as theconcrete will support necessary weight, the surface is covered with twolayers wet burlap one after the other; and these are maintained wetwithout drainage for 24 hours, when they are removed.

From the other approach expansion joint to expansion joint at aboutmidpoint line, the same procedures are followed except that, in solutionin the water added to regulate total water/cement ratio is added thesodium salt of dodecenylsuccinic acid in the amount of 0.25 percent bydry weight of non-latex concrete components.

From the entire area, traiiic is barred for 96 hours, whereupon serviceis restored.

Examination of the repaired bridge deck after two year's service revealsthat both repaired areas are of surfaces superior to those ofconventional concrete adjacent the bridge approaches; but that spallingand incipent spall cracks are more abundant in the area prepared withoutthe sodium dodecenylsuccinate: the ratio is about 18 spalled areas orwell-defined spall cracks in the area prepared without, to about 10spalled areas or spall cracks in the area prepared with the sodiumdodecenylsuccinate.

Example 35 A mortar mixture is prepared, of a dry, commercial magnesiumoxychloride cement powder which is composed of approximately equalweights of magnesium oxide (light burn) and magnesium chloride, togetherwith silica sand in the amount of twice the weight of oxychloride cementpowder. To this mixture water is added, sufficient to render it plastic;and it is then promptly applied as a cement to bind a'slate floor to aprepared underfloor.

The underfloor is of clean, sound plywood, swabbed with a commercialpentachlorophenol wood preservative solution, covered with buildersasphalt-impregnated felt paper that is secured conformingly into place;and over it at a distance of about Vs inch above the asphalted paper,expanded metal lath. The slate is pre-cut, clean, and moist.

In prompt procedures following the addition of water to the cementpowder, a cement base is laid down upon, and trowelled into and throughthe metal lath, and the upper surface struck off uniform.

Upon the mortar surface, present slate is bedded in, and the jointspaces between the pieces are nearly filled with further cement. Jointsurfaces are wiped to achieve uniformly struck finished joints. Thecement is permitted to harden during a week, as the mortar is keptmoist.

Thereafter, mortar joint surfaces are permitted to evaporate to drynessin air, and the present invention is applied to part of the slate-pavedarea.

In more particular, a solution is made, of mixed alkenyl succinic acids,notably hexadecenylsuccinic with an unassayed, small fraction oftctradecenylsuccinic acid, at a concentration of 5 percent by weight ofsolvent, in 1,1,1- trichloroethane.

The oxychloride cement mortar joints are left exposed as adjacent slateis covered with pressure-sensitive mask; ing tape and paper. Over theexposed joints the ASA solu tion is applied as a cone spray under airpressure to the point of incipient wetness. By penetration andevaporation the surface wetness quickly disappears. The ASA solution ispermitted to *dry during two days during which the cement furtherhardens. The joints are then water wetted and allowed to stand a day,and then tested.

Representative joints are found to be in tact, when challenged byhammering firmly with a fist, in both treated and untreated areas. Allof the slates were attached and none is detached.

A mop-water is prepared, of a. sodium linear alkylbenzenesulfonate inthe amount of about 0.1 weight percent of mop-water, together with about0.2 weight percent 15 water-soluble glassy sodium polyphosphate, and 0.1weight percent 3,4,4'-tribromosalicylanilide as germicide.

The mop-water is applied to portions of the treated and untreated areasof the slate floor, used in a scrubbing operation, and largely removedtherefrom, during repeated passes by a commercial wet vacuum cleanerwith floor brush engaged.

Thereafter, the resulting scrubbed surfaces are examined for visibleeffect, if any, of the wet vacuum cleaning of the treated and untreatedareas.

In the unscrubbed areas, the mortar of the wiped mortar joints proceedsin a smooth curve from the wiped depths of the joint to approachabutting slate edges smoothly, disappearing at infinitesimal thicknessat or near the upper edge of the slate flooring pieces. The samesituation prevails in the treated, scrubbed area.

Example 36 In this example, active agent is sodium hydrogenndecenylsuccinate; it is employed by admixing it with dry, unhydrated,powdered gypsum (i.e. Plaster of Paris) having reinforcing glass fiberstherethrough in an amount equal to 0.15 percent by weight of gypsumthereafter, working promptly and employing pilot plant equipment of thesort known in the developmental studies of the building materialsindustry, water in amount suitable to the orderly hydration of thegypsum is added thereto and promptly mixed thereinto, to obtain abriefly spreadable, rapidly hydrating paste. This is mechanically spreadand doctored smooth over an unrolling heavy paper; a second heavy paperis unrolled over the doctored surface of the gypsum paste and pressedagainst it by roller, to obtain an incompletely cured gypsum wall broadmodified according to this invention. The resulting board is carried ona slowly moving fabric belt over a period of an hour to achievepreliminary cure and is thereafter dried at gentle oven heat.

The resulting board is compared with a gypsum board of the prior art byemploying one board of this invention and a board of the prior artidentical except employing no ASA, in exterior building construction ina geographic 1 6 region characterized by annual rainfall of about 36inches. In this climate the boards, mounted side by side and givenessentially identical weather exposure are left without pro- ;iection ofany kind to ascertain their apparent serviceable ves.

What is claimed is:

1. A composition of matter adapted to be cured upon hydration to obtaina solid consisting essentially of a cementitious material and from 0.025to about 5 parts per parts of said material of an alltenyl succinicacid, an alkenyl succinic anhydride or a mixture thereof wherein eachalkenyl substituent is an independently selected alkenyl group of from 6to 16 carbon atoms.

2. Composition of claim 1 wherein the cementitious material is ahydraulic cement.

3. Composition of claim 2 wherein the hydraulic cement is portlandcement. I

4. Composition of claim 3 wherein the composition is a mixture of earthsoil and portland cement.

5. Composition of claim 3 wherein the composition is a mixture ofmineral aggregate and portland cement.

6. Composition of claim 2 wherein the hydraulic cement is lime.

7. Composition of claim 6 wherein the hydraulic cement is a mixture ofearth soil and lime.

References Cited UNITED STATES PATENTS 3,335,018 8/1967 Peeler et a1.106-90 3,202,521 8/1965 Lorenzen 106-90 3,131,074 4/ 1964 Thompson106-63 2,790,724 4/1957 Bergman 106-90 2,770,077 11/ 1956 Smith 47-582,491,045 12/1949 Holmes 106-94 2,113,375 4/1938 Himsworth 106-111 JAMESE. POER, Primary Examiner US. Cl. X.R.

